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Ridge, Rake, and Eaves

Most panel suppliers offer standard ridge components for use with their panels. These come in two varieties. One type has a formed flange to nest with the panels. While this type is easier to seal, the installer must keep the panel ribs perfectly aligned on both sides of the ridge. The other type has a flat flange that overlays the panels, and a closure strip is added. With both ridge types, use a sealant tape to seal the joint between roof panel and ridge cap. When using long panels that are subject to substantial thermal movement, make sure the ridge cap and the panels are fastened separately to the deck. Rake flashing. Prefabricated rake flashings are also available from the panel supplier. However, these are usually too large and "boxy" to use on a residence. Instead, ask the panel supplier to furnish flat sheet stock with a matching finish. You can then take the flat material to a local sheet metal shop, and have it bent into a simple L-flashing, as shown in Figure 5.

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Figure 5.

Rake flashings are fabricated from flat sheet stock provided by the roof panel manufacturer. Extend the horizontal leg of the flashing so it attaches with butyl tape and screws to the roof at a high rib. Ideally, this flashing should attach to the roof at a high rib with sealant, even if this means extending the horizontal leg a few extra inches. Fasten the rake flashing to the fascia. This is best done using a metal cleat that matches the angle of the drip leg. Or, you can fasten through the face of the flashing with a washered screw. Eaves flashing. Bend a simple drip edge for the eaves, as shown in Figure 6.

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Figure 6.

When gutters are used, seal the eaves as if they will be submerged in water. Use rubber closure strips sealed on all sides with butyl tape to prevent snow, rain, and vermin from entering the panel voids. Without gutters, roof panels should overhang the drip edge at least 4 inches. This drip flashing should be nailed down just enough to hold it in place prior to installing the roof panels. When the roof panels are installed, the screws should pierce the panel, drip flashing, and deck. Use eaves closures to prevent snow, rain, and vermin from entering the panel voids. Again, use tape sealants in conjunction with the closures, especially in severe climates. If gutters are used, take extra care when installing tape sealants and eaves closures. Freezing gutters and ice dams at eaves can cause serious moisture problems. If you seal the eaves edges to withstand occasional submersion in water, you'll never be disappointed or accused of misjudgment. If gutters are not used, the roof panels should overhang the drip edge by at least 4 inches.